title: Sagittal changes in lower incisors by the use of lingual arch.
abstract: OBJECTIVE
  The objective of this study was to evaluate a sagittal variation on the lower incisors with the use of the lingual arch on the transition from mixed to permanent dentition.
  
  
  METHODS
  The sample was constituted of 44 Caucasian patients (26 girls and 18 boys), divided in two groups: CG, control group, monitoring the lower arch space with no orthodontic/orthopedic treatment during the rated period (n = 14); EG, experimental group, presenting anterior inferior mild crowding and installation of the lingual arch for space maintenance (n = 30). The position of the lower incisors was analyzed on computerized cephalometric tracings performed at the beginning of the monitoring (T1) and at the end, on the permanent dentition (T2). In order to evaluate the position of the incisors it was used Tweed and Steiner measurements: IMPA, 1.NB and 1-NB. The alterations were analyzed through the "t" test for paired samples, while the differences between the groups were analyzed through the "t" test for independent samples, as for sexual dimorphism.
  
  
  RESULTS
  The values in T2 were greater in relation to T1 for all measurements on EG (IMPA, p = 0.038; 1.NB, p = 0.007 and 1-NB, p < 0.0001). On comparing the differences (T2-T1) between CG and EG, it can be gauged differences significantly superior for measure 1.NB (p = 0.002) and 1-NB (p < 0.0001) on EG. There was no statistically significant difference between genres.
  
  
  CONCLUSIONS
  It was concluded that the lower incisors were projected after using the lingual arch to control the space on the transition from mixed to permanent dentition, however, within acceptable standards, not having difference between genres.
authors.forename: Helen Carolina Becker
authors.initials: HC
authors.lastname: Letti
authors.forename: Susana Maria Deon
authors.initials: SM
authors.lastname: Rizzatto
authors.forename: Luciane Macedo
authors.initials: LM
authors.lastname: de Menezes
authors.forename: Chalana Sangalli
authors.initials: CS
authors.lastname: Reale
authors.forename: Eduardo Martinelli
authors.initials: EM
authors.lastname: de Lima
authors.forename: Fernando Lima
authors.initials: FL
authors.lastname: Martinelli
mesh_terms: D002508:Cephalometry; D002648:Child; D003818:Dentition, Mixed; D019229:Dentition, Permanent; D005260:Female; D006801:Humans; D007180:Incisor / Q000503:physiopathology*; D008297:Male; D008310:Malocclusion / Q000628:therapy*; D008334:Mandible; D017289:Orthodontic Appliances, Functional; D013027:Space Maintenance, Orthodontic / Q000295:instrumentation; D014087:Tooth Movement Techniques / Q000295:instrumentation*
keywords: Cranial circumference; Incisor; Orthodontics